Semiconductor component having an edge termination means with high field blocking capability

ABSTRACT

An n- or p-doped semiconductor region accommodates the depletion zone of an active area of the semiconductor component with a vertical extension dependent upon an applied blocking voltage. The junction termination for the active area is constituted with a semiconductor doped oppositely to the semiconductor region, and is arranged immediately adjacently around the active area on or in a surface of the semiconductor region. The lateral extension of the junction termination is greater than the maximum vertical extension of the depletion zone, and the semiconductor region as well as the junction termination are constituted with a semiconductor with a band gap of at least 2 eV.

FIELD OF THE INVENTION

The present invention relates to a semiconductor component.

BACKGROUND INFORMATION

A semiconductor component generally contains at least one activesemiconductor area with one semiconductor region of n- or p-typeconductivity as the drift region and two electrodes, associated withthis drift region, for applying an operating voltage to the driftregion, as well as generally further semiconductor regions forconfiguring component-specific semiconductor structures. With thecomponent in a conductive state, the drift region carries the electricalcurrent of charge carriers between the two electrodes. With thecomponent in the blocked state, however, the drift region accommodatesthe depletion zone of a p-n junction or blocking metal/semiconductorcontact (Schottky contact), constituted with the drift region, whichforms as a result of the high (as compared with the conductive state)operating voltages that are then applied. The depletion zone is oftenreferred to as the volume charge zone or blocking layer.

A distinction is made between unipolarly active and bipolarly activesemiconductor areas. With unipolarly active semiconductor areas only onetype of charge carriers, electrons or holes, defines operation; whilewith bipolarly active semiconductor areas both charge carrier types,i.e. electrons and holes, contribute to operation.

In the blocked state, comparatively high electric fields occur at thesurface of the component. It must therefore be ensured that theseelectric fields at the surface transition in a stable fashion into themedium surrounding the component, with a maximum field strength thatlies well below the breakdown field strength of the surrounding medium.The surrounding medium can be dielectric layers for isolation and/orpassivation, or a surrounding gas, generally air. The problem ofexcessive field strengths at the surface of a component occurs inparticular at high blocking voltages such as in the case of applicationsin power electronics, small dimensions with high field line curvatures,or high doping levels of semiconductor areas. To reduce field strengthsat the surface of a component, a "junction termination" is used, whichis produced in the surface of the component and surrounds the activearea of the component. The function of a junction termination consists,in addition to electrical shielding of the active semiconductor areafrom the outside, in also reducing field line curvatures around theactive semiconductor area in order to decrease excessive field strengthsin the area near the surface inside the semiconductor component.

A variety of embodiments of junction terminations for p-n junctions insilicon-based high-voltage components are known from the book "ModernPower Devices" by B. J. Baliga, John Wiley and Sons (USA), 1987, pp.79-129. P-n junctions of this kind are usually produced by diffusing adopant into one surface of a silicon layer as the drift region, thediffused region being of the opposite conductivity type to the siliconlayer. At the edge of the diffused region there occurs, because of thefield line curvature and as a function of the depth of this region, anexcessive field strength as compared to the planar p-n junction.

As is known, "floating field rings," which are produced annularly aroundthe diffused region of the p-n junction in the silicon layer, also bydiffusion, can be provided as the junction termination. These floatingfield rings are of the same conductivity type as the diffused region ofthe p-n junction, and are separated from one another by the oppositelydoped silicon layer. One or more floating field rings can be provided.

A second method of obtaining a junction termination consists in takingaway material, and therefore charges, around the edge of the p-njunction by mechanical removal or etching ("beveled-edge termination" or"etch contour terminations"). This produces mesa structures as thejunction terminations.

A third known junction termination for a p-n junction is a "fieldplate." For this, an oxide layer and upon it a metal layer are appliedonto an edge area around the p-n junction as the field plate. A field,with which the surface potential at the edge of the p-n junction ismodified. is applied to the metal layer. As a result, the depletion zoneof the p-n junction can also be expanded, and thus the field as well.The field plate can also be constituted with an electrode layer,associated with the p-n junction in order to apply an operating voltage,that overlaps the oxide layer in the edge area around the p-n junction.A junction termination can also be formed by a combination of floatingfield rings and field plates ("Modern Power Devices," page 119).

A fourth known embodiment of a junction termination is based on theprocess, complementary to the removal of charges, of controlled additionof opposite charges by ion implantation into the surface of the siliconlayer provided as the drift region, and is referred to as "junctiontermination extension." The implanted region is of the same conductortype as the diffused semiconductor region, and therefore dopedoppositely to the drift region, and has a lower doping level than thediffused region. Instead of being constituted with a region diffusedinto the drift region, the p-n junction can also be constituted with asilicon layer arranged on the surface of the drift region and dopedoppositely to the drift region. Ion implantation of the junctiontermination then occurs at the edge of the two layers constituting thep-n junction. The p-n junction is in practice extended by this junctiontermination, the electric field is expanded, and field curvature isdiminished. The breakdown resistance of the component is thus increased.This "junction termination extension" is proposed for bipolartransistors (BJTs), field-effect transistors (MOSFETs), and thyristors(SCRs--silicon controlled rectifiers) ("Modern Power Devices," page128). Because of the additional parasitic diode created with thisjunction termination, considerable bipolar leakage currents occur due tocharge carrier injection when the component is in the blocked state,especially in unipolar MOSFETs made of silicon. These leakage currentsbecome even greater if the junction termination is enlarged, sincecharge carrier injection increases with surface area.

A further junction termination comparable to this "junction terminationextension" is known from Swiss Application No. 659542, and is referredto there as a blocking layer elongation area. This junction terminationis provided for a p-n junction as the bipolarly active semiconductorarea of a semiconductor component, and can be produced by ionimplantation or epitaxial growth. The lateral extension (W_(JER)) of theblocking layer elongation area is made greater than approximately halfthe depletion width (W_(id)) of the low-doped side of the p-n junction.At values for lateral extension (W_(JER)) greater than twice thedepletion width (W_(id)), no further improvement occurs.

Silicon carbide (SiC) is a semiconductor material that is outstandinglysuitable, because of its electrical and thermo properties, in particularfor high-temperature and power electronics. In silicon carbide, forexample, the maximum possible field strength (breakdown field strength)is higher by a factor of about 10, and geometrical dimensions cantherefore be made smaller by a factor of about 10, than in silicon.

A power MOSFET constituted in silicon carbide as the semiconductor, withfloating field rings and field plates as junction termination, is knownfrom U.S. Pat. No. 5,233,215. The active area of the MOSFET isconstituted with a p-doped first epitaxial layer on an n⁻ -dopedsubstrate and a second n⁺ -doped epitaxial layer. The junctiontermination for the active area is configured as a mesa structure of thetwo epitaxial layers, produced by etching trenches that extend throughthe two epitaxial layers. Mesa structures as the junction termination,however, reduce the blocking voltage of the silicon carbide componentmade possible by doping of the semiconductor areas, due to high electricfields near the surface of the component. This increases the powerdissipation in the component.

It is thus the object of the present invention to indicate asemiconductor component with a junction termination. The junctiontermination is intended not to substantially raise the leakage currentof the component in its blocking state.

SUMMARY OF THE INVENTION

At least one semiconductor region of a first conductivity type isprovided, preferably extended laterally in the direction of its surface.This semiconductor region accommodates, in an active area of thecomponent in the blocking state, a depletion zone with a vertical (i.e.extending substantially perpendicular to the surface of thesemiconductor region) extension dependent upon the blocking voltage, andis thus provided as the drift region. A junction termination for theactive region is constituted with at least one further semiconductorregion of the opposite conductivity type to the drift regionaccommodating the depletion zone, and is arranged immediately laterallyadjacent to the active are, and surrounds the entire active area, onesurface of the junction termination being in one plane with the surfaceof the drift region.

The lateral extension of the junction termination is greater than themaximum vertical extension of the depletion zone, i.e. the maximumdepletion zone depth, in the drift region. According to the presentinvention, a comparatively large-area p-n junction, constituted betweenthe junction termination and drift region, is thus incorporated into thesemiconductor component. Due to the clearing of charge carriers out ofthe volume charge zone of this incorporated p-n junction, the electricfield is expanded in the area of the surface of the drift region, and atthe same time the active area of the semiconductor component is almostcompletely shielded from external charges and fields. An avalanchebreakdown occurs reliably in the bulk material, remote from the surfaceof the semiconductor region. One particular advantage of the largerlateral extension of the junction termination as compared to thevertical extension of the depletion zone consists in the fact that thebreakdown voltage of the semiconductor component is much less sensitiveto fluctuations in doping or in general to the charge carrierconcentration in the junction termination.

Semiconductors with a band gap of at least 2 eV are provided in eachcase as the semiconductors for the drift region and the junctiontermination. As a result, blocking-state currents when the semiconductorcomponent is in the blocking state are kept low, in particular even athigher temperatures, since the parasitic diode formed by the junctiontermination and drift region is not activated even at high blockingvoltages in the active area and at high temperatures, and as a result nominority charge carriers can be injected into the drift region. Inaddition, the voltage drop across a unipolarly active area in conductivemode remains below the voltage drop of the parasitic diode between thejunction termination and drift region. The unipolar component cantherefore be operated substantially without stored charge.

The combination of features according to the present invention providesan effective junction termination for electrical shielding of the activearea of a semiconductor component, even at high blocking voltages.

By adjusting the vertical extension and/or the doping profile of thejunction termination, the extension of the depletion zone of the p-njunction formed by junction termination and drift region, and thus theexpansion of the electric field at the surface, can be further adaptedin order to increase even further the breakdown resistance andadjustment tolerance of the semiconductor component.

A first embodiment of the semiconductor component according to thepresent invention provides that the lateral extension of the junctiontermination is greater by a factor of at least five than the maximumvertical extension of the volume charge zone accommodated by thesemiconductor region.

In a second embodiment of the present invention, the junctiontermination comprises at least two semiconductor areas of differentdoping. As a result a softer, i.e. smoother, expansion of the electricfield can be achieved. With a junction termination of this kind, dopedin multiple stages, the semiconductor component is particularly robustwith regard to manufacturing tolerances. The at least two semiconductorareas can be arranged vertically above one another, or laterally next toone another.

In a further embodiment of the present invention, the junctiontermination is grown epitaxially on the surface of the semiconductorregion provided as the drift region. The junction termination can,however, also be produced by ion implantation. These two approaches tomanufacturing the junction termination allow a precise adjustment of thedoping profile, especially of the doping height, and of the depth (i.e.vertical extension) of the junction termination.

The junction termination according to the present invention can be usedfor a semiconductor component with a unipolarly active area, for examplea metal-insulator semiconductor field effect transistor (MISFET)structure or a Schottky diode structure, or also for a semiconductorcomponent with a bipolarly active areas, for example a p-n diode, or anIGBT, GTO, or thyristor structure.

In a further embodiment of the present invention, an electrical contactassociated with the active area of the semiconductor component can alsoat least partially overlap the junction termination. As a result, thejunction termination can be set to a defined potential.

Preferably the drift region and the junction termination are made ofsilicon carbide (SiC). This yields a component suitable for particularlyhigh blocking voltages. Doping of the junction termination with boron isparticularly advantageous in this embodiment. The blocking effectivenessof the junction termination is then particularly high.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a general structure of a semiconductor component witha junction termination, according to an embodiment of the presentinvention.

FIG. 2 illustrates a semiconductor component with a junction terminationfor a Schottky diode structure, according to another embodiment of thepresent invention.

FIG. 3 illustrates a semiconductor component with a junction terminationfor a p-n diode structure, according to the present invention.

FIG. 4 illustrates a semiconductor component with a junction terminationwith two differently doped semiconductor areas for a MISFET structure,according to yet another embodiment of the present invention.

FIG. 5 illustrates a diagram of breakdown voltage as a function ofdoping of the junction termination.

FIG. 6 illustrates a field distribution in a semiconductor componentwith a Schottky diode structure.

DETAILED DESCRIPTION

FIG. 1 shows, in cross section, the general structure of a semiconductorcomponent with a junction termination according to the presentinvention. Reference symbols are 2 for a semiconductor region, 3 for anelectronically active area, 4 for the junction termination for thisactive area 3, 20 for a surface of semiconductor region 2, and 21 for adepletion zone formed in semiconductor region 2.

Semiconductor region 2 constitutes the drift region of the semiconductorcomponent, and accommodates, in active area 3 of the semiconductorcomponent when the latter is in the blocking state, depletion zone 21 ofactive area 3. This depletion zone 21 can be the volume charge zone of ap-n junction, constituted in active area 3 with semiconductor region 2,between two semiconductors of opposite conductor type, or the blockinglayer of a Schottky contact between a metal and a semiconductor. Thevertical extension--i.e. oriented substantially perpendicular to surface20 of semiconductor area 2--of depletion zone 21 is dependent on ablocking voltage applied in active area 3 by means of electrodes (notshown). The maximum vertical extension of depletion zone 21corresponding to a predefined blocking voltage is labeled T.Semiconductor region 2 is of greater extent in at least one lateraldirection--i.e. running substantially parallel to its surface 20--thanin the vertical direction. Semiconductor region 2 is generally arrangedon a substrate (not shown), for example an epitaxially grownsemiconductor layer.

Junction termination 4 for active area 3 of the semiconductor componentis arranged on surface 20 of semiconductor region 2. Junctiontermination 4 is immediately laterally adjacent to active area 3, andsurrounds the entire active area 3. The lateral extension of junctiontermination 4, labeled W, is greater than the maximum vertical extensionT of depletion zone 21 in semiconductor region 2. Preferably, lateralextension W of junction termination 4 is at least five times as great asthe maximum vertical extension T of depletion zone 21. For a depletionzone extension T of, for example 10 μm, lateral extension W of junctiontermination 4 is preferably made to be between 50 μm and 150 μm.Vertical extension d of junction termination 4 is preferablysubstantially constant.

Furthermore, junction termination 4 is constituted with at least onesemiconductor of the opposite conductivity type to semiconductor region2. In the embodiment depicted, semiconductor region 2 is n-typeconductive, and junction termination 4 is p-type conductive, with ap-type conductive semiconductor region 2, on the other hand, an n-typeconductive junction termination 4 is to be provided. Preferably junctiontermination 4 is produced by ion implantation of dopant particles intosurface 20 of semiconductor region 2, or by growing onto surface 20 ofsemiconductor region 2 an epitaxial layer to be correspondingly doped.

Semiconductor region 2 and junction termination 4 are each constitutedwith at least one semiconductor with a band gap of at least 2 eV.Suitable semiconductor materials are, for example, boron nitride (BN),boron phosphide (BP), aluminum phosphide (ALP), gallium phosphide (GAP),zinc sulfide (ZnS), or diamond (C). Silicon carbide (SiC) in all itspolytypes, but in particular the 6H, 4H, and 3C polytype, isparticularly suitable because of its outstanding electronic properties.

With a junction termination 4 as shown in FIG. 1, a comparativelylarge-area p-n junction is incorporated into the semiconductor componentin the area of surface 20 of semiconductor region 2. The volume chargezone of this p-n junction that forms with the semiconductor component inthe blocking state on the one hand shields active area 3 andsemiconductor region 2 from electric fields and charges from outside thecomponent, and on the other hand leads to an expansion of the electricfield in the area of surface 20. The breakdown resistance of thecomponent is thus raised, and higher blocking voltages can be applied toactive area 3. Because of the high band gap (at least 2 eV), as comparedwith silicon (Si), of the semiconductor or semiconductors used, thelarge-area p-n diode constituted with junction termination 4 andsemiconductor region 2 has a high built-in voltage and is not activatedeven at high blocking voltages. Junction termination 4 thereforegenerates essentially no additional blocking currents in thesemiconductor component. The achievable blocking voltages are thereforemuch higher than in silicon. The built-in voltage of a p-n junctionconfigured in SiC is, for example, greater than approximately 2.6 V.

FIG. 2 depicts, in cross section, part of an embodiment of asemiconductor component with at least one Schottky diode structure 33 asthe unipolarly active area. Arranged on a substrate 9 made of an n-dopedsemiconductor is an epitaxially grown semiconductor layer, also n-doped,as the semiconductor region 2. This epitaxial layer is generally lessdoped than substrate 9. Substrate 9 does not need to consist of asemiconductor with a high band gap, and can, for example, also beconstituted with silicon, especially if semiconductor region 2 isconstituted with silicon carbide. Schottky diode structure 33 contains acontact 25, arranged on surface 20 of semiconductor region 2 andgenerally metallic, as the Schottky contact. The blocking layer ofSchottky diode structure 33 that forms beneath contact 25 insemiconductor region 2 when a blocking voltage is applied constitutesdepletion zone 21 in the active region of the semiconductor component.An epitaxially grown p-doped semiconductor layer is arranged onsemiconductor region 2, immediately adjacent to contact 25, as thejunction termination 4. The semiconductor layer constituting junctiontermination 4 is of considerably greater extension in its layer plane(lateral extension W) than the layer thickness of semiconductor region2, and therefore also than the maximum vertical extension T of depletionzone Junction termination 4 can extend as far as the edge ofsemiconductor region 2. Contact 25 is preferably also arranged on aportion of junction termination 4 (overlapping contact). In addition,semiconductor region 2 and junction termination 4 can also be equippedat their outer edges, facing away from the active region, with a recess23, for example a beveled-etch edge. When silicon carbide is used as thesemiconductor for Schottky diode structure 33 and its junctiontermination 4, blocking voltages of up to 1200 V can be applied, forexample at a doping of n=10¹⁶ cm⁻³ for semiconductor region 2. Inconductive mode, the voltage drop between contact 25 and a furtherelectrode (not shown) in Schottky diode structure 33 remains below thevoltage drop of the parasitic p-n diode between junction termination 4and semiconductor region 2. This ensures that the unipolar componentoperates substantially without stored charge.

A portion of a semiconductor component with at least one p-n diodestructure 36 as the bipolarly active area is shown in cross-section inFIG. 3. Semiconductor region 2 is grown epitaxially on a semiconductorsubstrate 9, and is of the same conductivity type (n-type) as substrate9. The p-n junction of p-n diode structure 36 is constituted with then-type semiconductor region 2 and a p-type semiconductor region 26,preferably epitaxially grown, on surface 20 of semiconductor region 2.Arranged on this p-type semiconductor region 26 is an ohmic contact 27.In this case the volume charge zone of the p-n junction of p-n diodestructure 36 constitutes depletion zone 21 of the active area. A p-typesemiconductor layer, preferably epitaxially grown onto surface 20 ofsemiconductor area 2, is provided as junction termination 4 for p-ndiode structure 36. This semiconductor layer of junction termination 4is directly adjacent to the p-type semiconductor region 26 of p-n diodestructure 36. Ohmic contact 27 can again partially overlap junctiontermination 4.

In addition, a recess 23 can again be provided at the edge ofsemiconductor region 2. Ion-implanted semiconductor regions can ofcourse also be provided instead of epitaxially grown semiconductorregions.

FIG. 4 illustrates a semiconductor component with at least one MISFETstructure 37 as another embodiment of the present invention with aunipolarly active area. The n-doped semiconductor region 2 arranged onthe n⁺ -doped substrate 9 represents the drift region of MISFETstructure 37. MISFET structure 37 comprises at least one p-doped baseregion 50 generated in surface 20 of semiconductor region 2 by ionimplantation or diffusion; at least one source region 51 generatedwithin base region 50, also by ion implantation or diffusion; at leastone source electrode 52 of source S, by means of which source region 51and base region 50 are electrically short-circuited; a gate electrode 54of gate G (insulated gate), electrically insulated by means of aninsulator layer 53 and arranged above a channel region of base region 50that connects source region 51 and semiconductor region 2; and a drainelectrode 55 of drain D arranged on the side of substrate 9 facing awayfrom semiconductor region 2. Depletion zone 21 of the p-n junctionconstituted between base region 50 and semiconductor region 2,accommodated by semiconductor region 2, is indicated schematically.MISFET structure 37 can, as shown in FIG. 4, be made up of individualcells each with a base region 50 and at least one source region 51, withassociated source electrode 52 and insulated gate electrodes 54 bridgingthe individual Cells. Junction termination 4 for MISFET structure 37 isimmediately adjacent to base region 50 located at the outer edge ofMISFET structure 37, and is, like base region 50, doped oppositely tosemiconductor region 2. Junction termination 4 is preferably produced byion implantation of dopant particles into surface 20 of thesemiconductor region. Junction termination 4 and/or base region 50 ofMISFET structure 37 can, however, also be epitaxial layers.

In the embodiment of the present invention as shown in FIG. 4, junctiontermination 4 is made up of at least two differently doped semiconductorregions 41 and 42. These two semiconductor regions 41 and 42 arearranged laterally next to one another on surface 20 of semiconductorregion 2, and preferably are either both implanted or diffused, or bothepitaxially grown. Preferably both semiconductor regions 41 and 42 haveapproximately the same vertical extension. Semiconductor region 41immediately alongside MISFET structure 37 has lower doping (p-) thanadjoining base region 50 of MISFET structure 7, and higher doping thanthe p⁻ -doped semiconductor region 2 that is laterally adjacent on theside facing away from said base region 50. A junction termination 4 witha graduated doping is thus obtained. In an advantageous embodiment ofthe present invention, lateral extension W1 of first semiconductorregion 41 is made smaller than lateral extension W2 of secondsemiconductor region 42. The total lateral extension W of junctiontermination 4 is then the sum of the individual extensions W1 and W2 ofthe two semiconductor regions 41 and 42. This total lateral extension Wof junction termination 4 is again made greater than the maximumvertical extension T of depletion zone 21 of MISFET structure 37.

In yet another embodiment of the present invention (not shown), the twosemiconductor regions 41 and 42 can be arranged vertically above oneanother. A vertical structure of this time can, for example, be producedby ion implantation or diffusion with differing penetration depths, orby epitaxially growing the semiconductor regions sequentially above oneanother. The semiconductor region arranged below then advantageously haslower doping than the semiconductor region arranged below. Lateralextension W of the junction termination is then determined substantiallyby the greatest lateral extension of the individual semiconductorregions arranged vertically above one another. Preferably the lateralextensions of all the semiconductor regions are at least approximatelythe same size.

Furthermore, the junction termination can also consist of a lateral or avertical arrangement of more than two semiconductor regions, eachdifferently doped, such that the doping preferably decreases laterallyoutward or vertically downward.

Multistage junction terminations of this kind are not confined tosemiconductor components with MISFET structures, but can also beprovided for all other semiconductor components. These junctionterminations with multistage doping have the advantage that the electricfield in the vicinity of surface 20 of semiconductor region 2 assumes asmoother profile outward from the active region.

It is understood that in all the embodiments of the present inventiondescribed so far, the conductivity types of all semiconductor regionscan be respectively reversed.

FIGS. 5 and 6 show the results of numerical, computer-aided simulationsof semiconductor components with junction terminations according to thepresent invention. The calculations are based on SiC as thesemiconductor material for the semiconductor component.

As shown in FIG. 5, the breakdown voltage V of the semiconductorcomponent is plotted as a function of the logarithmically plotted dopinglevel p of the (single-stage) junction termination 4 of thesemiconductor component, using three different vertical extensions d ofjunction termination 4 as parameters and for a predefined lateralextension W of junction termination 4. The solid curve labeled V1corresponds to a vertical extension d=2 μm, dashed curve V2 to avertical extension d 3D 0.7 μm, and dot-dash curve V3 to a verticalextension d 3D 0.3 μm of junction termination 4. Each of the threecurves shows pronounced maxima in a certain doping range. In thevicinity of these maxima, breakdown voltage V of the semiconductorcomponent is practically equal to the ideal, theoretically possiblebreakdown voltage V0 in the bulk material of the semiconductorcomponent. As vertical extension d of junction termination 4 decreases,the maxima are shifted toward higher doping levels and become broader(note the logarithmic plot used for doping level p). By adjustingvertical extension d of junction termination 4, it is thus possible tomake the semiconductor component more robust in terms of manufacturingtolerances during doping of junction termination 4.

The qualitative plot of breakdown voltage V as a function of doping p(or n) of junction termination 4 depicted in FIG. 5 is largelyindependent of the structure of the active area, and also of the dopingof semiconductor region 2 of the semiconductor component, and can beobserved with the embodiments according to FIGS. 1 to 4.

Vertical extension d of junction termination 4 is typically between 0.1μm and 5 μm.

FIG. 6 shows a field distribution that is possible with junctiontermination 4 according to the present invention, using the example of asemiconductor component with a Schottky diode structure 33 shown in FIG.2. The scales plotted on the x and y axes indicate size relationshipsand dimensions. The electric field lines are drawn with dashed lines.

When silicon carbide (SiC) is used as the semiconductor material,junction termination 4 is preferably p-doped with boron (B) or withaluminum (Al), or n-doped with nitrogen (N). Boron (B) is particularlyadvantageous as a dopant for junction termination 4, since the boronatoms form deep acceptor levels in SiC. In this embodiment of thepresent invention, junction termination 4 can handle particularly highblocking voltages.

In all embodiments, additional passivation layers made of dielectric orsemi-insulating materials can be provided in addition to junctiontermination 4. With a semiconductor component based on SiC, thepassivation layers can in particular consist of amorphous SiC, silicon(Si), or carbon (c).

What is claimed is:
 1. A semiconductor component comprising:at least onesemiconductor region including at least one first semiconductor having afirst conductivity type, the at least one semiconductor region having aregion width and a region height, the region width being greater thanthe region height; an active area including a depletion zone extendinginto the at least one semiconductor region and having a depletion zoneheight being dependent on a blocking voltage applied to the active area;and a junction termination member having a junction termination widthand including at least one second semiconductor having a secondconductivity type which is opposite in polarity to the firstconductivity type, the junction termination member surrounding andpositioned laterally adjacent to the active area, the junctiontermination member having a junction surface which is coplanar with asemiconductor region surface of the semiconductor region, wherein thejunction termination width of the junction termination member is greaterthan the depletion zone height of the depletion zone, and wherein thefirst semiconductor and the second semiconductor each have a band gap ofat least 2 eV.
 2. The semiconductor component according to claim 1,wherein the junction termination width of the junction terminationmember is at least five times as large as the depletion zone height ofthe depletion zone.
 3. The semiconductor component according to claim 1,wherein the junction termination member is epitaxially grown on thesurface of the semiconductor region.
 4. The semiconductor componentaccording to claim 1, wherein the junction termination member is formedby ion implantation.
 5. The semiconductor component according to claim1, further comprising an electrical contact associated with the activearea, the electrical contact at least partially overlapping the junctiontermination member.
 6. The semiconductor component according to claim 1,wherein the active area is a unipolar active area.
 7. The semiconductorcomponent according to claim 1, wherein the active area is a bipolaractive area.
 8. The semiconductor component according to claim 1,wherein the first and the second semiconductors include silicon carbide.9. The semiconductor component according to claim 8, wherein thejunction termination member is doped with boron.
 10. The semiconductorcomponent according to claim 1, wherein the at least one secondsemiconductor has a first doping level and provides a maximum reverseblocking voltage at an optimum doping level corresponding to the firstdoping level, the first doping level being between one-third of theoptimum doping level and three-times the optimum doping level.
 11. Thesemiconductor component according to claim 1, wherein the junctiontermination member includes a junction height, the junction height beingless than one μm.
 12. A semiconductor component comprising:at least onesemiconductor region including at least one first semiconductor having afirst conductivity type, the at least one semiconductor region having aregion width and a region height, the region width being greater thanthe region height; an active area including a depletion zone extendinginto the at least one semiconductor region and having a depletion zoneheight being dependent on a blocking voltage applied to the active area;and a junction termination member having a junction termination widthand including at least one second semiconductor having a secondconductivity type which is opposite in polarity to the firstconductivity type, the junction termination member surrounding andpositioned laterally adjacent to the active area, the junctiontermination member having a junction surface which is coplanar with asemiconductor region surface of the semiconductor region, wherein thejunction termination width of the junction termination member is greaterthan the depletion zone height of the depletion zone, and wherein thefirst semiconductor and the second semiconductor each have a band gap ofat least 2 eV, and wherein the junction termination member includes aplurality of semiconductor areas each having a different doping.
 13. Thesemiconductor component according to claim 12, wherein the plurality ofsemiconductor areas includes first and second semiconductor areas, thefirst semiconductor area being arranged laterally next to the secondsemiconductor area.
 14. The semiconductor component according to claim12, wherein the plurality of semiconductor areas includes first andsecond semiconductor areas, the first semiconductor area being arrangedabove the second semiconductor area.
 15. A semiconductor componentcomprising:at least one active area including a depletion zone, thedepletion zone having a depletion zone vertical extension beingdependent on a blocking voltage applied to the at least one active area;at least one semiconductor region of a first conductivity type extendingin a lateral direction and in a vertical direction, the depletion zoneextending into the at least one semiconductor region, the at least onesemiconductor region extending further in the lateral direction than inthe vertical direction, the vertical direction being perpendicular tothe lateral direction; and a junction termination member associated withthe active area, the junction termination member including at least onesemiconductor of a second conductivity type which is opposite inpolarity to the first conductivity type, the junction termination membersurrounding positioned laterally adjacent to the at least one activearea, the junction termination member having a junction surface which iscoplanar with a semiconductor region surface of the semiconductorregion, wherein the junction termination member includes a junctionlateral extension, the junction lateral extension being larger than thedepletion zone vertical extension of the depletion zone, and wherein thesemiconductor region and the junction termination member are each formedwith at least one second semiconductor, the semiconductor region and thejunction termination each having a band gap of at least 2 eV.
 16. Thesemiconductor component according to claim 15, wherein the junctionlateral extension of the junction termination member is at least fivetimes as large as the depletion zone vertical extension of the depletionzone.
 17. The semiconductor component according to claim 15, wherein thejunction termination member is epitaxially grown on the surface of thesemiconductor region.
 18. The semiconductor component according to claim15, wherein the junction termination member is formed by ionimplantation.
 19. The semiconductor component according to claim 15,further comprising an electrical contact associated with the at leastone active area, the electrical contact at least partially overlappingthe junction termination member.
 20. The semiconductor componentaccording to claim 15, wherein the at least one active area is aunipolar active area.
 21. The semiconductor component according to claim15, wherein the at least one active area is a bipolar active area. 22.The semiconductor component according to claim 15, wherein thesemiconductor region and the junction termination include siliconcarbide.
 23. The semiconductor component according to claim 22, whereinthe junction termination member is doped with boron.
 24. Thesemiconductor component according to claim 15, wherein the at least onesecond semiconductor has a first doping level and provides a maximumreverse blocking voltage at an optimum doping level corresponding to thefirst doping level, the first doping level being between one-third ofthe optimum doping level and three-times the optimum doping level. 25.The semiconductor component according to claim 15, wherein the junctiontermination member includes a junction height, the junction height beingless than one μm.
 26. A semiconductor component comprising:at least oneactive area including a depletion zone, the depletion zone having adepletion zone vertical extension being dependent on a blocking voltageapplied to the at least one active area; at least one semiconductorregion of a first conductivity type extending in a lateral direction andin a vertical direction, the depletion zone extending into the at leastone semiconductor region, the at least one semiconductor regionextending further in the lateral direction than in the verticaldirection, the vertical direction being perpendicular to the lateraldirection; and a junction termination member associated with the activearea, the junction termination member including at least onesemiconductor of a second conductivity type which is opposite inpolarity to the first conductivity type, the junction termination membersurrounding and positioned laterally adjacent to the at least one activearea, the junction termination member having a junction surface which iscoplanar with a semiconductor region surface of the semiconductorregion, wherein the junction termination member includes a junctionlateral extension, the junction lateral extension being larger than thedepletion zone vertical extension of the depletion zone, and wherein thesemiconductor region and the junction termination member are each formedwith at least one second semiconductor, the semiconductor region and thejunction termination each having a band gap of at least 2 eV, andwherein the junction termination member includes a plurality ofsemiconductor areas each having a different doping.
 27. Thesemiconductor component according to claim 26, wherein the plurality ofsemiconductor areas includes first and second semiconductor areas, thefirst semiconductor area being arranged laterally next to the secondsemiconductor area.
 28. The semiconductor component according to claim26, wherein the plurality of semiconductor areas includes first andsecond semiconductor areas, the first semiconductor area being arrangedabove the second semiconductor area.